Caffeine, both sides of the coin

I have used and recommended green tea for its incredible health benefits.

Tea, primarily black, is the most widely consumed beverage on the planet. Coffee drinking is also popular worldwide. The National Soft Drink Association of America estimates on average each citizen drinks more than 600 12-ounce servings of soft drinks per year. All these beverages have a common constituent - caffeine. Is caffeine good or bad?

What is caffeine?

Caffeine is a naturally occurring substance found in many plants, including coffee beans, tea leaves and cocoa nuts. However, in these natural foods, the caffeine exists not in isolation but in combination with hundreds of other active substances which modulate the actions of caffeine. Mother Nature uses this to create her own checks and balances that we often override by isolating and concentrating just on the caffeine.

Medically, caffeine is used to stimulate the heart, to dilate the breathing passages in conditions like asthma and also as a mild diuretic to increase urine production.

Socially and culturally, it is used to provide an energy boost or to create a feeling of heightened alertness. Caffeine by itself is a nervous system stimulant and is potentially addictive, as some effects are similar to those of the amphetamine drugs. High doses of caffeine can excessively stimulate the heart and nervous system.

Caffeine in the Diet

The most common everyday sources of caffeine are:

Tea: Black tea (in regular tea bags) contains 70 mg per six-ounce cup. Green tea contains 30 mg per six-ounce cup.

Coffee: Typical drip-brewed coffee contains 100 mg per six-ounce cup. If you are buying your coffee at a restaurant or fast-food outlet or drink it at home or the office out of a mug, you are consuming it in 12, 14 or 20-ounce containers. You can calculate the number of milligrams based on your serving size.

Other drinks: Red Bull contains 80mg per 8 ounce can; generally, colas (Coca-Cola, Pepsi, etc.) contain about 50mg per 12-ounce servings cocoa or hot chocolate contains 20mg per six-ounce cup; typical milk chocolate contains 6mg per ounce;

Medicines: Anacin contains 32mg per tablet; No-doze contains 100mg per tablet; Dexatrim contains 200mg per tablet.

Benefits of Caffeine

Caffeine has been shown to improve alertness and concentration. Studies suggest it helps some night-shift workers to maintain concentration, potentially reducing the chances of industrial accidents.

Research indicates that athletes who consume 300 mg (equivalent to three six-ounce cups of coffee), 30 minutes before a workout experience up to 30 per cent improvement in endurance with faster times, less exertion, less fatigue and more rapid recovery.

Caffeine for weight loss

Caffeine is commonly found in many diet pills, as it breaks down fat into fatty acids, which are easily burned to produce energy. Conversion of fat to energy is about 30 per cent more efficient when caffeine is consumed prior to exercise. Since this breakdown and burning occurs only when you exercise, caffeine alone has limited usefulness for weight loss.

Caffeinated Soft Drinks and Children

Modern kids drink a lot of caffeinated soft drinks. A high caffeine intake is bad for children. It actually dissolves the calcium in young bones. When a group of teenagers drank an unsweetened caffeinated drink, the calcium loss in their urine increased by 25 per cent. Sugary, caffeinated drinks, made their calcium loss even higher.

The Best Source of Caffeine

Phosphorus, found in most carbonated soft drinks, accelerates bone loss even more. One soda costs a child as much as 120mg of calcium. Furthermore, a soft drink after exercise also depletes children's sodium, chloride, and potassium levels, causing sore muscles and delayed reco-very time after exercise.

Caffeine is potentially useful, but how much you consume and where you get it from is very important. I believe that the best source of caffeine is green tea. Green tea contains much smaller quantities of caffeine than coffee or black tea. It has a powerful energising and fat-burning effect due to other substances it contains.

Green tea contains potent antioxidants called polyphenols that can prevent cancers like prostate, breast and intestinal cancer. It also has a long list of other health benefits from lowering cholesterol to preventing tooth decay.

In addition to being energising, green tea also has an anxiety relieving effect. This is due to the presence of a substance called treanine that appears unique to teas.

Caffeine is best and safest when used as a part of balanced nutritional regime like the Cellular Nutrition programme. Excess sugar, as well as vitamin and mineral deficiencies, may promote sensitivity to caffeine.

When used wisely and in moderation, caffeine can have many health benefits and I recommend that you get it from a green tea concentrate.

You may email Dr Tony Vendryes at vendryes@mac.com or listen to 'An Ounce of Prevention' on POWER 106FM on Fridays at 8 p.m. The programme streams live on the Internet.